Flip-Flop Mobile Phone

1. A flip-flop electronic device, comprising: a first casing having a first pivot portion, wherein the first pivot portion has a first sleeve; a first friction means, which is a slide notch disposed on an outside surface of the first sleeve; a second casing having a second pivot portion, wherein the second pivot portion has a second sleeve receiving the first sleeve, so that the second casing rotates relative to the first casing; and a second friction means, which is a protruding member disposed on an inner surface of the second sleeve; wherein when the second casing rotates at a predetermined angle relative to the first casing, the protruding member is inserted into the slide notch to form a friction fit between the sliding notch and the protruding member to decrease an angular velocity of the rotating second casing.

2. The flip-flop electronic device according to claim 1 , wherein the slide notch comprises a bottom surface and a plurality of side wall for contacting the protruding member to decrease the angular velocity of the second casing.

3. The flip-flop electronic device according to claim 1 , wherein the slide notch comprises a wedge-shaped opening for guiding the protruding member into the slide notch.

4. The flip-flop electronic device according to claim 1 , further comprising a tightening mechanism, which comprises: a third friction means disposed at one end of the first sleeve and opposite to the slide notch, the third friction means being axially movable along the first sleeve; an elastic means disposed at the other end of the first sleeve and being opposite to the third friction means; and a lock coupled with the first sleeve to allow the elastic means sustaining the third friction means, the protruding member being inserted into the slide notch and contact with the third friction means when the second casing rotates at the predetermined angle relative to the first casing.

5. The flip-flop electronic device according to claim 4 , wherein the third friction means is a cannular block, and the cannular block is mounted at one end of the first sleeve.

6. The flip-flop electronic device according to claim 4 , wherein the elastic means is a spring, and the spring is disposed at the other end of the first sleeve.

7. The flip-flop electronic device according to claim 4 , wherein the lock is a screw.

8. The flip-flop electronic device according to claim 1 , wherein a rotating angle is determined by a position of the slide notch on the outside surface of the first sleeve and by a position of the protruding member on inner surface of the second sleeve.

9. The flip-flop electronic device according to claim 1 , wherein the first casing is a main body and the second casing is a lifting cover.

10. The flip-flop electronic device according to claim 1 , wherein the flip-flop electronic device is a flip-flop mobile phone.

11. A flip-flop electronic device, comprising: a main body having a first pivot portion, and the first pivot portion having a slide notch; and a lifting cover having a second pivot portion, the second pivot portion being pivotally connected with the first pivot portion so that the lifting cover can rotate relative to the main body, and the second pivot portion having a protruding member; wherein when the lifting cover rotates at a predetermined angle relative to the main body, the protruding member is inserted into the slide notch so that a friction made by the sliding notch and the protruding member decreases an angular velocity of the lifting cover.

12. The flip-flop electronic device according to claim 11 , wherein the slide notch comprises a bottom surface and a plurality of side wall for contacting the protruding member to decrease the angular velocity of the lifting cover.

13. The flip-flop electronic device according to claim 11 , wherein the slide notch comprises a wedge-shaped opening for guiding the protruding member into the slide notch.

14. The flip-flop electronic device according to claim 11 , wherein the flip-flop electronic device further comprises a tightening mechanism including: a cannular block mounted at one end of the first pivot portion and being pivotally moveable relative to the slide notch; a spring mounted at the other end of the first pivot portion and being opposite to the cannular block; and a screw coupling with the first pivot portion to allow the spring sustaining the cannular block, wherein the protruding member is inserted into the slide notch and contacts with the cannular block, when the lifting cover rotates at the predetermined angle relative to the main body.

15. The flip-flop electronic device according to claim 11 , wherein the flip-flop electronic device is a flip-flop mobile phone.

16. A flip-flop electronic device, comprising: a first casing having a first pivot portion; a first friction means disposed on the first pivot portion; a second casing having a second pivot portion, the second pivot portion being pivotally connected with the first pivot portion so that the second casing rotates relative to the first casing; and a second friction means disposed on the second pivot portion; wherein when the second casing rotates at a predetermined angle relative to the first casing, at least one surface of the first friction means contacts at least one surface of the second friction means, a contacting area between the at least one surface of the first friction means and the at least one surface of the second friction means increases as the angle between the second casing and the first casing increases from a closed status to an open status of the flip-flop electronic device.

17. The flip-flop electronic device according to claim 16 , wherein the first friction means is a slide notch, the second friction means is a protruding member, and when the second casing rotates at the predetermined angle relative to the first casing, the protruding member is inserted into the slide notch to form a friction fit between the sliding notch and the protruding member.

18. The flip-flop electronic device according to claim 17 , wherein the first pivot portion has a first sleeve with the slide notch disposed on an outside surface thereof, and the second pivot portion has a second sleeve with the protruding member disposed on an inner surface thereof so that the second pivot portion is pivotally connected with the first pivot portion by mounting the second sleeve on the first sleeve.